/**
 * Pointer Aliasing
 * Julien Etienne, 2008
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <stdio.h>

/**
 * Prints the contents of a float and an int.
 */
void myPrint(float *pf, int *pi){
	printf("float *pf = %f (at address %p); int *pi = %d (0x%x) (at address %p)\n", *pf, pf, *pi, *pi, pi);
}

int main(
	int argc __attribute__((unused)),	/* Remove the attribute unused warning */
	char **args __attribute__((unused))
	){
	float f = 1.0f;

	/* Show the size of the datatypes we use */
	printf("sizeof(float) = %d\nsizeof(int) = %d\n", sizeof(float), sizeof(int));

	/* pf and pi points to the same memory address
	 * but using different datatype to trigger aliasing issue.
	 */
	float *pf = &f;
	int   *pi = (int*)pf;

	/* Print the content pointed by both pointers */
	myPrint(pf,pi);

	/* Change the value to see if both pointers see the change */
	f=2.0f;
	myPrint(pf,pi);

	return EXIT_SUCCESS;
}

